Metal sandwiches

State or vibrational energies. If the current across the metal-insulator-metal sandwich is recorded as a function of applied voltage, the current increases as the threshold for each state or vibrational mode is crossed. The increases in current are in fact very small, and for improved detectability the current is double-differentiated with respect to voltage, thereby providing, in effect, a vibrational spectrum that can be compared directly with free-molecule IR and Raman spectra. 

Metal sandwich complexes of cyclic, planar and pyramidal ligands containing boron. R. N. Grimes, Coord. Chem. Rev., 1979, 28, 47-96 (132). 

Warren KD (1984) Calculations of the Jahn-Teller Coupling Constants for d Systems in Octahedral Symmetry via the Angular Overlap Model. 57 119-145 Warren KD (1977) Ligand Field Theory off-Orbital Sandwich Complexes. 33 97-137 Warren KD (1976) Ligand Field Theory of Metal Sandwich Complexes. 27 45-159 Watson RE, Perlman ML (1975) X-Ray Photoelectron Spectroscopy. Application to Metals and Alloys. 24 83-132... 

Recent work on [CpFe(CO)2]2 was intended to test whether once again a complex molecule could be found to have a high yield and also to test a possible preferential formation of metal carbonyls over metal sandwich compounds. In this compound, thermal decomposition of the starting compound gives rise predominantly to ferrocene (28, 68). The data (50) given in Table VIII show that indeed the carbonyl is preferentially formed... 

Warren, K. D. Ligand Field Theory of Metal Sandwich Complexes. Vol. 27, pp. 45-159. 

Ligand Field Theory of Metal Sandwich Complexes... 

In principle it should be possible to determine the anisotropy of the paramagnetic susceptibility for some systems of pseudo-axial symmetry, but apart from the citation (74) of a private communication regarding the ferricenium cation, no experimental data are available for metal sandwich complexes. Such measurements should however be possible for at least some metallocenes and mixed sandwich complexes since these are found to crystallise in either a monoclinic (Fe(Cp)2 (6)) or orthorhombic (Ru(Cp)2, (Cp)V(Ch),... 

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